<!DOCTYPE html>
<html lang="en" xmlns:v-bind="http://www.w3.org/1999/xhtml" xmlns:v-on="http://www.w3.org/1999/xhtml">
<head>
    <meta charset="UTF-8">
    <title>Title</title>

</head>
<body>

<div id="app">
    <button v-on:click="sayHi">点我</button>
</div>


<!--1.导入vue.js-->
<script src="https://cdn.jsdelivr.net/npm/vue@2.5.21/dist/vue.min.js"></script>
<script>
    var vm = new Vue({
        el: '#app',
        data: {
            message: 'hello,Vue!'
        },
        methods: {
            sayHi:function() {
                alert(this.message)
            }
        }
    });
</script>
</body>
</html>